[Qemu-devel] [PATCH v2 5/6] qmp: Support abstract classes on device-list-properties

[Eduardo Habkost <ehabkost@redhat.com>]

When an abstract class is used on device-list-properties, we can
simply return the class properties registered for the class.

This will be useful if management software needs to query for CPU
options that are supported by all CPU models, for example.

Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
---
 qmp.c | 21 +++++++++------------
 1 file changed, 9 insertions(+), 12 deletions(-)

diff --git a/qmp.c b/qmp.c
index b3ba9ef..dd6090d 100644
--- a/qmp.c
+++ b/qmp.c
@@ -518,7 +518,7 @@ DevicePropertyInfoList *qmp_device_list_properties(const char *typename,
                                                    Error **errp)
 {
     ObjectClass *klass;
-    Object *obj;
+    Object *obj = NULL;
     ObjectProperty *prop;
     ObjectPropertyIterator iter;
     DevicePropertyInfoList *prop_list = NULL;
@@ -537,19 +537,16 @@ DevicePropertyInfoList *qmp_device_list_properties(const char *typename,
     }
 
     if (object_class_is_abstract(klass)) {
-        error_setg(errp, QERR_INVALID_PARAMETER_VALUE, "name",
-                   "non-abstract device type");
-        return NULL;
-    }
-
-    if (DEVICE_CLASS(klass)->cannot_destroy_with_object_finalize_yet) {
-        error_setg(errp, "Can't list properties of device '%s'", typename);
-        return NULL;
+        object_class_property_iter_init(&iter, klass);
+    } else {
+        if (DEVICE_CLASS(klass)->cannot_destroy_with_object_finalize_yet) {
+            error_setg(errp, "Can't list properties of device '%s'", typename);
+            return NULL;
+        }
+        obj = object_new(typename);
+        object_property_iter_init(&iter, obj);
     }
 
-    obj = object_new(typename);
-
-    object_property_iter_init(&iter, obj);
     while ((prop = object_property_iter_next(&iter))) {
         DevicePropertyInfo *info;
         DevicePropertyInfoList *entry;
-- 
2.7.4